SIR Alex Ferguson has blasted back at John Magnier and JP McManus by claiming it is 'incomprehensible' that he would abuse his position at Manchester United.

Ferguson has also revealed that son Jason has been forced to call in the police amid allegations that his mail was being stolen.

The long-serving United chief feels his integrity has been called into question by Magnier and McManus, who wrote to club chairman Sir Roy Gardner requesting answers to 99 questions, mainly concerning the role of agents in 15 recent transfers.

Though Irish sources insist the demand for an independent audit of the club's transfers has nothing to do with Ferguson's dispute with Magnier over the stud rights to record-breaking stallion Rock of Gibraltar, the United board believe the opposite to be true.

Outburst

And, having signed his new rolling contract on Wednesday, Ferguson has now decided to enter the fray with an emotional outburst.

"This is distressing," he said.

"My son has had a terrible time. People have been stealing his mail, going through his bin bags and hiding in bushes. In the end he has had to call the police in.

"It is all a result of what we are reading about in terms of the transfer stuff.

"It is incomprehensible that I would abuse my position at this club. I have been here 17-and-a-half years and nobody has ever raised a doubt about that."